Porocyphus
| Porocyphus | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lichinomycetes |
| Order: | Lichinales |
| Family: | Lichinaceae |
| Genus: | Porocyphus Körb. (1855) |
| Type species | |
| Porocyphus coccodes (Flot.) Körb. (1855)
| |
| Synonyms[1] | |
Porocyphus is a genus of lichen-forming fungi in the family Lichinaceae.[5] The genus was established in 1855 by the German lichenologist Gustav Wilhelm Körber to distinguish certain lichens from the related genus Collema, based on differences in their reproductive structures. Porocyphus species are found worldwide and are characterised by their pore-like fruiting bodies and simple spores. They form dark, gelatinous crusts on rocks, soil, and bark.
Taxonomy
[edit]The genus Porocyphus was circumscribed the German lichenologist Gustav Wilhelm Körber in 1855 to accommodate certain gymnocarpous lichens (lichens with exposed fruiting bodies) that had previously been classified under Collema. Körber distinguished Porocyphus from Collema based on the distinctive nature of the apothecia, particularly the differences in thallus structure and the characteristics of the hymenial layer and paraphyses. The genus name is derived from the Greek words πόρος ('pore', 'passage') and κύφος ('hump', 'swelling'), referring to the small tubercular fruiting bodies. Körber noted that while the external form of the apothecia and the stratified thallus structure might suggest placement within Collema, the distinctive ostiole of the apothecia and nuclear characteristics warranted generic separation, emphasizing the gymnocarpous nature of these lichens.[6]
Description
[edit]Porocyphus forms a dark, gelatinous crust that clings tightly to rock, soil or bark. Its surface can appear as a scatter of tiny grains, cracked areoles, diminutive leaf-like patches or, in some species, minute shrub-like tufts bearing granular outgrowths (isidia). Because the lichen lacks a true outer skin (cortex) and any internal layering, the fungal threads (hyphae) run directly through the thallus. Near the point of attachment those hyphae often pack into a narrow brick-like band, while elsewhere they fan out like water from a fountain, each short cell radiating from the base. The photosynthetic partner is from the cyanobacterial genus Calothrix; its usual long filaments are so fragmented inside the lichen that they often resemble solitary cells, yet they still provide the dual benefits of photosynthesis and nitrogen fixation.[7]
Sexual fruit bodies (apothecia) develop either in the ordinary way or by transforming tiny asexual chambers (pycnidia) into so-called pycnoascocarps. They start out buried in the thallus and become flush with the surface or slightly stalked as they mature. A persistent rim of thallus tissue (the thalline margin) commonly surrounds the pore-like disc, though this rim may erode with age to expose the inner fungal wall (exciple). The exciple is colourless to pale brown and conspicuous above but tapers below. Inside, a colourless or faintly brown base supports a spore layer threaded with densely branched, interconnected paraphyses; in pycnoascocarps these may mingle with elongated conidiophores left over from the asexual stage. Chemical tests with iodine stain the gelatinous matrix from yellow to blue, yet the asci themselves show no amyloid reaction and lack the thickened tips seen in many lichens. Each ascus usually contains eight simple, ellipsoidal ascospores that have no internal walls or outer gelatinous coat. Asexual reproduction still occurs in separate pycnidia, which sit immersed in the thallus or in tiny warts; they release colourless, spherical to short-ellipsoid conidia. Thin-layer chromatography has revealed no secondary lichen substances, so the genus is diagnosed chiefly by its gelatinous, dark thallus with Calothrix photobiont, its pore-like apothecia that may arise from pycnidia, and its simple, non-septate spores.[7]
Species
[edit]- Porocyphus antarcticus (Cromb.) M.Schultz & M.Prieto (2024)[8]
- Porocyphus coccodes Flot. ex Körb. (1855)
- Porocyphus kalbarriensis Henssen (1990)
- Porocyphus kenmorensis (H.B.Holl ex Nyl.) Henssen (1974)
- Porocyphus leptogiella (Nyl.) T.L.Ellis (1981)[9]
- Porocyphus lichinelloides Henssen (1963)[10]
- Porocyphus macrosporus (Henssen, Büdel & Wessels) M.Schultz & M.Prieto (2024)[8]
- Porocyphus minutissimus (Henssen) M.Schultz (2024)[8]
- Porocyphus rehmicus (A.Massal.) Zahlbr. (1924)[11]
- Porocyphus rosulans (Henssen) M.Schultz (2024)[8]
- Porocyphus tasmanicus (Henssen) M.Schultz (2024)[8]
- Porocyphus willeyi (Tuck.) M.Schultz & M.Prieto (2024)[8]
References
[edit]- ^ "Synonymy. Current Name: Porocyphus Körb., Syst. lich. germ. (Breslau): 425 (1855)". Species Fungorum. Retrieved 18 June 2025.
- ^ Nylander, W. (1881). "Addenda nova ad Lichenographiam europaeam. Contin. XXXV". Flora (in Latin). 64: 2–8 [6].
- ^ Nylander, W. (1881). "Addenda nova ad Lichenographiam europaeam. Continuatio quadragesima septima" [New additions to European lichenography. Forty-seventh continuation]. Flora (Regensburg). 70: 129–136.
- ^ Ciferri, R.; Tomaselli, R. (1953). "Saggio di una sistematica micolichenologica" [Essay on a mycolichenological systematics]. Atti del'Istituto Botanico e del Laboratorio Crittogamico dell'Università di Pavia. 10 (1): 25–84.
- ^ "Porocyphus". Catalogue of Life. Species 2000: Leiden, the Netherlands. Retrieved 18 June 2025.
- ^ Körber, G.W. (1855). Systema lichenum Germaniae [System of the lichens of Germany] (in Latin). Breslau: Trewendt & Granier. p. 425.
- ^ a b Cannon, P.; Coppins, B.; Sanderson, N.; Simkin, J. (2023). Lichinales: Lichinaceae and Peltulaceae, including the genera Cryptothele, Ephebe, Euopsis, Lemmopsis, Lempholemma, Lichina, Metamelanea, Peltula, Phylliscum, Porocyphus, Psorotichia, Pterygiopsis, Pyrenocarpon, Pyrenopsis, Synalissa, Thermutis and Watsoniomyces (PDF). Revisions of British and Irish Lichens. Vol. 44. pp. 4–5.
- ^ a b c d e f Prieto, M.; Wedin, M.; Schultz, M. (2024). "Phylogeny, evolution and a re-classification of the Lichinomycetes". Studies in Mycology. 109 (1): 595–655. doi:10.3114/sim.2024.109.09. PMC 11663425. PMID 39717657.
- ^ Ellis, L.T. (1981). "A revision and review of Lemmopsis and some related species". The Lichenologist. 13 (2): 123–139. Bibcode:1981ThLic..13..123E. doi:10.1017/S0024282981000170.
- ^ Henssen, A. (1963). "Eine Revision der Flechtenfamilien Lichinaceae und Ephebaceae" [A revision of the lichen families Lichinaceae and Ephebaceae]. Symbolae Botanicae Upsalienses (in German). 18 (1): 1–123 [68].
- ^ Zahlbruckner, A. (1924). Catalogus Lichenum Universalis (in Latin). Vol. 2. Leipzig: Verlag von Gebrüder Borntraeger. p. 765.
